(·银川高三二模)It remains to be seen this plan is practical enough to keep the project goi

问题补充：

(·银川高三二模)It remains to be seen this plan is practical enough to keep the project going.

A. whether

B. how

C. where

D. when

答案：

(答案→)A. whether

B. how

C. where

D. when

解析：选A考查主语从句。句意：这个计划是否足够实用，以使这个项目继续下去还有待观察。it是形式主语，真正的主语是whether引导的从句。whether“是否”，符合句意。